Flexible tube.



No. 817,059. PATENTED APR. 3, 1906.

E. T. GREENFIELD. FLEXIBLE TUBE.

APPLICATION FILED APR.1Z.1905.

WITNESSES: g INVENTOR UNITED sTArns 'r TE T OFFICE.

- FLEXIBLE TUBE,

, specification of Letterslatent,

Patented April 3, 1906.

Application filed April 12, 1905. Serial'llo. 265,148 I Tomi/Z whom it may concern;-

7 Be it known that I, EDWIN T. GREENFIELD,

a citizen of the United States, residing at' Monticello, county of Sullivan, and State of New York, havemade a new and useful Invention in Flexible Tubes, of which the fol-- lowingis a specification.

My invention is directed particularly 'to improvements in flexible tubes constructed of one or more spirally-wound interlocking strips of metal-such, for instance, as is disclosed .in numerous United States patents heretofore granted to me; and it has forjits objects, first, the construction of such a tube in such manner as to give to the same great strength with the desired flexibility and in such manner as to be water and gas tight under extreme pressures and under all conditions of usage second .the construction of such a tube from a single strip of metal with a spirally-disposed spring gasketbetween theinterlocking parts and of such material as, will withstand reat heat and be of great durability; third, the construction of such a tube with a spirally-wound spring-gasket be tween the outer locking ed ge of the inner part and the-innersurface of the outer'pa'rt, said gasket'bein g adapted to yieldingly withstand lndefinite wear and strain, thus enabling it to be-used as a hose or conveying-pipe under" conditions where enormous pressures are transmitted and at practically all temperatures' r For a full and clear understanding of m invention, such as will enable others skilled in the art to construct the same, reference is had to the accompanying drawings, in whichugure 1 is apart longitudinal sectional part side elevational vview of a short sectionv of tube constructed in accordance with 1n improvement. Fig. 2 is an enlarged. detail sectional view showing the relation of the interlocking parts and the spring-gasket when the. tube is in normal condition, and Fig. 3 is a'similar view illustrating the same when the tube is put under abending strain. 4

1 represents a spirally-disposed strip of metal having a substantially S cross-section and constructed, preferably, in the manner disclosed in prior patents heretofore granted 'to me, by forcing a-strip of steel and the sealing-gaskets through a screw-threaded die, which will give to it the-conformation just indicated and willalso edges thereof to interlock in the manner shown, the inner portion of the strip having No. 367,301, granted cause the overlapping include such a structural certained that a flexible tube constructed in the cross-sectional curved formation indi cated and the outer portion thereof a rectangularconformation, such that when the tube is bent the outer or exposed locking edge Wlll bear upon the curved portion and move In each instance in a radlus extending from a the axial center ofthe tube, as indicatedin dotted lines.

2 is a yielding orfiexible strip of non-oxidizable metal, referably bronzecopper, which has the fbrmation in cross-section material, preferably asbestos, located within the grooved portion of this stri the arrangement being such that when a 1 of the parts are formed and interconnected in the manner shown thereresults an absolutely water or gas ti 'ht joint throughout the lengths of the spira s. The flexib e strip 2 is so constructed, as shown, that when the tube asshown, and 3 is a strip of packing or porous sumes any curvature the interior locking ed ge thereof rests upon the longitudinal center of this strip and moves in curves corresponding to the curvature indicated by the dotted. radiallines, the gasket as a whole assuming the conformation illustrated in Fig. 3. It'w1ll be' clear on inspection of the drawings that this gasket is located between the outer surface of the'entireint'erlocking edge of eachpart of thejcompleted tube and fills the entire inner surface of the tubular corrugations in the loop or body portion of the S-shaped construction in cross-section. Such a tube when thus constructed possesses the greatest flexibility and greatest possible strength when made of a steel strip of the desired crosssection.

I have ascertained that by reason of the. yielding nature of the'flexible strip 2 and the porous packing 3, which together constitute a sealing strip or duce an absolute y water and gas tight tube asket, I am enabledto pro-" of the greatest possible strength both as toits a power-to withstand radial pressure from the iquid orgas confined therein and as to the locking relation of the locking edges of the g g stri 1 am aware that heretofore a tube has been constructed of spirally-wound interlocking strips of metal] having gaskets of soft rubber between the interloc in United States patent to Herbert Knight, July 26, 1887, and I make no claim hereinafter broad enough to device)" I have as ung edges,vas disclosed the manner indicated in the before-mentioned patent deteriorates materially in use, particularly when hot water or steam is conveyed therethrough, for two reasons first, by reason of the rapid wear of the gasket, and, second, by reason of the vulcanization of the rubberwhile my improvement by reason of the yielding or spring nature of the metallic gasket and its inclosed porous medium possesses great strength, as before pointed out, and overcomes the objections novel flexible tube the gasket being of yiel above enumerated. Furthermore, with m ing material and located between the bearing-surfaces of the successive spirals it is rendered assuredly water and gas tight. Nor do 1 limit my novel tube to a single striparmor, as obviously two interlocking strips might be used with radially-disposed springgaskets. To illustrate, two springaskets might be used with the two interlocking spiral strips disclosed in the before-mentioned patent to Knight and come within the generic idea of my invention.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is'

1. A flexible tube constructed of a spirallywound metal strip having interlocking edges and a sealing-gasket located between the outer surface of the inner interlocking edge and the entire inner surface of the outer tubular part of the strip.

2. A flexible tube constructed of a spirallywound metal strip of substantially 8 crosssection; in combination with a sealingasket located between the entire inner su ace of one part of the strip and the outer or looking edge of the other part thereof.

3. A flexible tube constructed of a spirallywound strip of metal having interlockin edges and a flexible metallic gasket locate between the entire inner surface of one part and the interlocking edge of the next adjacent part.

4. A flexible tube constructed of a spirallywound stri of metal having a cross-section of substantially 8 form; in combination with a spirally-wound asket fillin the space between the interloc 'ng edges 0 the inner part and the interlocking inner surface of the outer part of the strip.

5. A flexible tube constructed of a spirallywound strip of metal having a cross-section of substantially 8 form, one part thereof being curved exteriorly in combination with a spirally-wound yieldin gasket between the outer surface of the-loo 'ng edge of said part and the entire inner surface of the other part.

6. A flexible tube constructed of spirallywound interlocking parts and a spirallywound gasket located between the outer surface of the locking edge of said part and the entire inner surface of the other part.

7. Aflexible tube made of spirally-disposed strip metal having interlockin edges; in combination with a spring-gas et located between the entire bearin -surfaces of the successive spirals, so that t e outward pressure of the confined liquid or gas holds all of the parts of the tube in firm contact and ren clers the same practically liquid and gas tight.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

EDWIN T. GREENFIELD.

Witnesses: C. J. KINTNER,

M. F. KEATING. 

